Analog Devices VisualDSP++ 5.0 Service Manual page 259

DI_EN
(Data Interrupt Enable)
• The
XCount
the number of elements to be transferred. For two-dimensional
transfers, this value defines the inner loop count (number of
columns).
• The
XModify
defines the address increment/decrement (stride) for each succes-
sive element. For two-dimensional transfers, this value defines the
inner loop address increment/decrement (stride) for each successive
element up to but not including the last element in each inner
loop. After the last element in each inner loop, the
applied instead, except on the very last element of the transfer.
• The
YCount
transfers. For two-dimensional transfers, the value represents the
outer loop count (number of rows).
• The
YModify
transfers. For two-dimensional transfers, this value defines the
outer loop address increment/decrement (stride) that is applied
after each inner loop completion. This value is the offset between
the last element of one row and the first element of the next row.
The DMA manager does not constrain when descriptors can be provided
to a channel. For DMA channels that process inbound data, it is best prac-
tice to provide descriptors to the channel via the
function before enabling dataflow. By doing this, the DMA controller uses
a space where data can be stored. If dataflow is enabled on an inbound
channel prior to providing descriptors, it is possible for data to be received
by the DMA channel but not have anywhere to store it.
VisualDSP++ 5.0 Device Drivers and System
Services Manual for Blackfin Processors
ADI_DMA_DI_EN_DISABLE
ADI_DMA_DI_EN_ENABLE
value. For one-dimensional transfers, this value defines
value. For one-dimensional transfers, this value
value. This parameter is ignored for one-dimensional
value. This parameter is ignored for one-dimensional
DMA Manager
No callback is generated.
The DMA manager generates a
callback to the client when the
transfer completes.
YModify
adi_dma_Queue()
value is
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